Schedule II (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Valuation and Qualifying Accounts Disclosure [Line Items]
Valuation Allowances and Reserves, Beginning Balance		$ 1.4	$ 1.6	$ 1.9
Valuation Allowances and Reserves, Charged to Cost and Expense		2.5	2.4	2.3
Valuation Allowances and Reserves, Deductions	[1]	2.4	2.6	2.6
Valuation Allowances and Reserves, Ending Balance		$ 1.5	$ 1.4	$ 1.6

[1] Uncollectible accounts receivable written off, net of recoveries.